The head of Northern Ireland's civil service is examining a court judgment that questioned the ability of officials to make major policy decisions in the absence of devolution.

The outcome of Monday's ruling in Belfast High Court, when a judge blocked a decision by a senior civil servant to approve a huge waste incinerator plant, could have major ramifications for how Northern Ireland's rudderless public services are run amid the ongoing powersharing impasse.

Senior civil servants have been taking the majority of decisions within departments since Stormont collapsed 16 months.

While the UK government has stepped in on occasion to make significant cross-governmental decisions, such as setting a budget and enabling the collecting of rates, the civil service has effectively been in charge, as Stormont exists in a limbo land between devolution and direct rule.

However, Mrs Justice Keegan, presiding in a judicial review case, found that Peter May, the permanent secretary of the Department for Infrastructure, did not have the power to approve the planning application for the £240 million incinerator facility on the old Hightown quarry site near Newtownabbey.

She said such a decision should have been made by elected ministers.

David Sterling, the head of the Northern Ireland Civil Service and the man running Stormont amid the impasse, is now assessing the impact of the judgment.

A spokesman for Mr Sterling and The Executive Office said: "We are considering today's judgment."

The Northern Ireland Office (NIO) said Secretary of State Karen Bradley was also considering the decision.

"No, I think direct rule would be disastrous for good government here in the north of Ireland," she said.

"I think whatever the differences between parties I think there is a recognition that the best answer is for local decisions that affect people's lives to be taken locally.

"Undoubtedly today's decision highlights yet again the absolute necessity to restore powersharing and for these institutions to work and these institutions can only work on the basis of real powersharing."

DUP MP Paul Girvan said: "This ruling has major implications for decision making in Northern Ireland.

"It shows that the lack of ministerial direction is unsustainable if we are to have significant decisions taken that affect the lives of people in Northern Ireland.

"The Government must move to put arrangements in place so that ministerial decisions can be properly taken.

"Sinn Fein has collapsed devolved government but Her Majesty's Government cannot allow Northern Ireland to grind to a complete halt. The people should not be punished because of Sinn Fein's narrow political agenda."

SDLP deputy leader Nichola Mallon said a question mark was now placed on other decisions that had been taken in the powersharing impasse.

"What has happened today is the courts have called time on the political drift in this place," she said.

"It has called into question significant decisions that have been taken by the civil service in the absence of an Assembly and we have requested an urgent meeting with the head of the civil service to understand the governance arrangements of this place."